JPS5945243A - Seat belt retractor - Google Patents

Abstract

PURPOSE:To improve the feeling of putting-on of a seat belt and heighten safety, by using a motor to wind the belt and by winding the loose belt to make it tight immediately after the putting-on of the belt and by giving a prescribed looseness to the belt after the tight winding, and by effecting looseness-giving control again under set conditions. CONSTITUTION:A worm wheel 16 is rotated through transmission means 19-21 by the rotarory power of a motor 18 secured on the upper part of a housing 11, to turn a winding shaft 12 for a belt 1. A central processing unit 24 controls the motor 18 through a transistor bridge circuit 27 so that the motor is rotated forward and backward. The CPU24 includes a comparator which compares a set value corresponding to a prescribed looseness of the belt 1, with the output of a displacement detector 23 which detects the displacement of the belt 1. The direction of the rotation of the motor 18 is controlled on the basis of the outputs of the comparator and a putting-on detector 52. Control for giving a looseness to the belt 1 is effected again when a prescribed time has elapsed after the putting-on of the belt or when the belt is pulled out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a belt retractor, and particularly to one in which a motor is used to take up and rewind a belt.

Conventionally, as a 7-toe belt retractor using a motor, there are, for example, those shown in Figs. 1 and 2 (
Special Publication No. 52-9891).

When the notebook belt I is pulled out and put on, this /- belt retractor rotates the motor 3 by the buckle engagement switch 2, and connects the worm l and fan-shaped gear 5 to the retractor via the lever 6 and stop 7. Rotate lever 8 in the belt loosening direction, let out the belt a certain length, and then turn lever 6.
The tension lock state is maintained by the engagement of the claw guard 7.

However, in such a conventional notebook belt retractor, the belt is wound up by a winding spring in the winder 8, so if a winding spring or a motor drive section is provided, the IJ l- The first problem is that the belt becomes complicated and large.
Since the rotation of the motor was controlled by a motor such as 0, and the belt was loosened by a certain amount from the state where the buckle switch 2 was turned on, if there was slack when the belt was attached, the amount of slack would increase further, and the notebook belt There was a second problem that the original function could no longer be fulfilled.

Regarding the first problem, a notebook belt retractor has been proposed in which the belt is retracted and even pulled out using only a motor, without using a retracting spring (Japanese Patent Application No. 57-27597). ), has already been resolved. However, even with this notebook belt retractor that retracts using only a motor, the excess belt is retracted and tightened with the buckle switch turned on, and then a predetermined amount of slack is added. Therefore, if there is slack during the tightening, the amount of slack will significantly exceed the predetermined amount.

As a result, the second problem of the notebook belt being unable to perform its original function has not been satisfactorily resolved.

Problems with this type of Chiku2 include cases where the seat belt is not in the best position when winding up and tightening the excess seat belt, or when the seat belt gets caught on the arm, or when the seat belt distorts the body. This is considered to be the cause, and it is thought that such a situation often occurs immediately after seating.

The present invention has been made based on this viewpoint and focusing on both the above-mentioned cause and the second problem. a motor that rotates the winding shaft in the winding direction; a displacement detection device that emits a signal corresponding to the rotation of the winding shaft and detects the displacement of the belt in the winding direction direction; a comparison device that compares a set value with the output signal of the displacement detection device; a mounting detection device that detects the notebook belt device; and a device that corrects the motor based on the output of the mounting detection device and the comparison device. A slack control device that performs winding tightening to wind up the excess belt after attaching the notebook belt by reversing the belt, and giving a predetermined slack after tightening the notebook belt, and a slack control device that performs tightening by winding the excess belt after attaching the notebook belt, and a slack control device that performs tightening to wind the excess belt after the notebook belt is attached, and a slack control device that performs tightening to wind the excess belt after tightening the notebook belt. and a means for reactivating the slack control device after sensing, the belt retractor is provided with a belt retractor that first winds and tightens the excess belt immediately after curing;
Then, after tightening the waistband, give a predetermined slack (hereinafter, these two consecutive actions are referred to as belt slack adjustment).Then, by adjusting the belt slack again under the set conditions, the above-mentioned problem can be solved. The purpose is to

The present invention will be explained below based on the drawings. Figures 3-4 show an embodiment of the present invention, in which reference numeral l] indicates a housing formed in a substantially U-shape; This is a winding shaft that is supported and to which one end of the belt I is fixed.

A known emergency lock mechanism 1 is provided at one end of the winding shaft L2 to prevent rotation of the winding shaft L2 in the pull-out direction in an emergency.
3 is provided.

In addition, a rotary angle detection model wheel 1 is provided on the protrusion at the other end of the winding shaft [2].
4 is fixed, further sandwiching the friction transmission spring 15,
A worm wheel 16 is loosely fitted in a rotatable manner. A snap ring 17 is engaged with the end of the winding shaft 2 to prevent the worm wheel 16 from being removed.

Reference numeral 18 denotes a motor identified at the upper part of the housing 11, and a rotating shaft 18a of this motor 18 protrudes rearward from the side plate 11a, to which a worm 19 is fixed. This worm 19 is meshed with a worm wheel 21 fixed to a shaft 20 which is disposed perpendicularly to the worm 19 on the side plate 11a and is rotatably supported. Furthermore,
A worm 22 meshed with a worm wheel 16 loosely fitted onto the winding shaft 2 is attached to the end of the shirt 20.
is fixed.

Therefore, when the t-motor 18 is rotated, the rotation is caused by the worm 19. Worm wheel 21. It is decelerated via the worm 22 and transmitted to the worm wheel 16 . The rotation of the worm wheel 16 is transmitted to the winding shaft 12 via the stop 14 due to the frictional force with the friction transmission spring 15.

23 is a displacement detection device using two 7-otocouplers,
It is fixed to the side plate 11a of the housing 11, emits a signal according to the rotation of the winding shaft, and detects the displacement of the belt in the winding direction and the pulling direction.

Next, FIG. 5 shows an embodiment in which a microcomputer is used as a slack control device and the like.

In the figure, 24 is a CPU of a microcomputer, which has an output port and a manual port, and is equipped with a ROM 25 for storing programs and constant data, and a RAM 26 for temporarily storing input signals, calculation results, etc. 1 is a transistor bridge circuit for controlling the motor 18 in the forward and reverse directions, and by rotating the motor 18 in the forward direction, the belt is wound up one time, and in the reverse direction (to provide appropriate slack). an input port 29 for inputting a signal from the vehicle speed pulse generator 5 for setting a value for imparting appropriate slack to the belt;
is ``ON'' when the tank sewn to the belt drawer end is engaged with the buckle (note belt attached), and °OF when it is not engaged (note belt not attached).
31.x is an input port for inputting a signal from the mounting detection device 52 which generates a switch signal which is "F", and 31.x is an input port for inputting a signal from the displacement detection device n for detecting the rotation angle of the retractor winding shaft [2] It is a human-powered boat.

In addition, the displacement detection device 23 is connected to the retractor's winding shaft [2] in the rotational direction (window viewing or drawing direction) shown in the detailed view of FIG.
It has a function of detecting the rotation angle and the relative position of the notebook belt.

(Incidentally, the displacement detection device can also use a variable resistance that is linked to the movement of the notebook belt.) Next, the comparison device,
A microcomputer incorporating a sag control device and means for reactivating the sag control device will therefore be described in further detail.

When the crew member is seated and the tank sewn to the end of the belt drawer is engaged with the buckle, and a signal is input from the input boat valley, the ■ ``buckle sw'' changes from OFF to ON, and the ■ ``belt sw'' changes from OFF to ON. In other cases, proceed to ``Tosoku Sensitive Slack Adjustment'' described later. This■
As shown in Figure 7 (b), ``belt slack adjustment'' involves two methods: ``sealing'' the excess belt that has been pulled out after wearing the belt and tightening it tightly against the body, and ``sagging'' tightening the belt at a predetermined tightening position. It consists of "belt stopping" to stop the belt, and "belt slackening" to loosen the belt by a predetermined length, and here the belt slackness is adjusted immediately after seating. That is, the motor 18 is rotated forward from the output boat via the transistor bridge I, the signal J+St of the input ports 31) and 31 is detected, the position where the belt is tightened to the tension state is defined as the belt tight position N, and then the position is adjusted to the appropriate position according to the vehicle speed. The amount of slack is applied to the belt by reversing the motor, and the timer Ts is set. The next ■ Drying/Drawing” is signal S,
, S, to detect whether or not the belt is being pulled out. Specifically, this pullout is performed when the passenger manually pulls out the belt to make it fit tightly against the body after adjusting the belt slack, or when the passenger leans forward. If there is a drawer, proceed to ``Re-adjust belt slack''; if there is no drawer, proceed to ``1'-Ts) 10 seconds''.

In other words, the timer is set to 10 seconds in this embodiment, and RAMX
The timer Ts in the table is checked, and if there is no drawer within a certain period of time after adjusting the belt slack immediately after the seat is seated, the process proceeds to (2) ``Re-adjusting the belt slack'' after this time has elapsed.

Therefore, the belt slack adjustment is performed again when the belt is pulled out after the first belt slack adjustment and after the timer setting time has elapsed. Also, ■ "Re-belt slack adjustment" works in the same way as ■ "Belt slack adjustment", and rotates the motor 18 in the normal direction from the output boat via the transistor bridge I, and detects the signal J * 82 of the human-powered boat x, 31. The tightened position in the tensioned state is defined as the belt tight position N, and then the belt is given an appropriate amount of slack depending on the vehicle speed by reversing the motor.

Then, in the next step ■``Vehicle speed sensitive slack amount adjustment'', process the subsequent vehicle speed (including slack adjustment, etc.), and ■``Buckle sw
OFF→ON" and repeat this routine. As for ■ "Drawer", it is also possible to make it respond only to reactions so that it does not react to small body movements, and ■ "Ts ) 10 seconds" timer processing is shown in Figure 9. This is generally performed using regular interrupt processing as shown.

As described above, according to this embodiment, even if the seat belt is not in the best position and the seat belt is already caught, the slack control device is reactivated, so that the seat belt remains in close contact with the occupant. function can be reliably demonstrated.

FIG. 8 shows a second invention, in which the degree of adhesion of the 7-belt is improved more than that shown in FIG. That is, the processes from (1) to (2) are similar to those shown in FIG. 7, and after the belt is installed, the belt is tightened and the end position is brought to the close contact position N. After that, the end position of the tightening performed in (1) "Drawing out" or (2) "Re-adjusting the belt slack" after the time set by the timer Ts has elapsed is defined as the close contact position @N2. ■ ``At N, -N, J, compare the previous close contact position @ 11 with the current close contact position N, and if N2-NI≧0, ■'``N←N,'' Proceed to N, and set the value of N as the true contact position N, N, -N.

If <0, proceed to ■N←N21 and set the value of N2 as the true contact position N.

In other words, whichever of the belt slack adjustment and re-belt slack adjustment, the length of the belt pulled out from the tractor at the close contact position is shorter, or if both values match, that value is determined as the more accurate close contact position, and this value is set as the more accurate close position. The true close contact position is N, and the N
This is used as the reference value for subsequent appropriate slackening.

Therefore, in ■ "Vehicle speed-sensitive slack adjustment", the belt slack adjustment is performed according to the vehicle speed based on the true load position N. This section Hp3 is compared to the one shown in Figure 7. It becomes more appropriate.

As explained above, the present invention includes a winding shaft to which the end of the belt is fixed, a motor that rotates the winding shaft in the winding direction or the drawing direction, and a motor that rotates the winding shaft in the direction of rotation of the shaft.
a displacement detection device that emits a signal with a difference of 1α and detects the displacement of the belt 1 in the winding direction and the pull-out direction; a value set corresponding to a predetermined belt slack; a comparison device that compares the output signal of the seatbelt with an output signal of the seatbelt, a mounting detection device that detects whether the seatbelt is worn, and a mounting detection device that rotates the motor forward or reverse based on the output of the mounting detection device and the comparison device, The tightening of winding the belt,
a slack control device that controls a predetermined slack after tightening the waistband;
Since the slack control device is provided with a means for reactivating the slack control device after a predetermined period of time has elapsed after the operation of the slack control device has ended, or after detecting that the belt has been pulled out, the occupant can In the 5th situation where the belt is pulled out after changing the posture, the belt can be re-loosened M176 @ in a better seating position for the occupant, and secondly, the belt can be loosened for a certain period of time after the initial belt slack adjustment. After the time has elapsed, the belt slack adjustment is performed again when the occupant's posture is adjusted. Therefore, by adjusting the belt slack again, a more optimal belt wearing condition can be obtained, which improves the feeling of wearing and safety. You can improve your performance. In addition, in the second invention shown in FIG. 8, the close contact position that becomes the reference value when adjusting the belt slack is automatically selected as the one with a high degree of belt tightness, so it is not preferable to adjust the belt slack again. in case of,
Better tightness and position (6,
The belt slack can be adjusted based on the standard, and the wearing comfort and safety can be further improved.

[Brief explanation of the drawing]

Fig. 1 is a drowsiness circuit diagram showing an example of a conventional 7-tovel l-IJ tractor, Fig. 2 is a schematic configuration diagram thereof, and Fig. 3 is an example of the configuration of a 7-tovel tractor according to the present invention. 4 is a side view thereof, FIG. 5 is a diagram of an embodiment of the slack control device neck etc. using a microcomputer of the present invention, FIG. 6 is a detailed configuration diagram of a displacement detection device, and FIG. 7
Figure (A) is a flowchart showing one embodiment of the control program of the present invention, Figure 7 (B) is a partially detailed view of Figure 7 (A), and Figure 8 is a flowchart showing an embodiment of the control program of the present invention. FIG. 9 is a flowchart showing an example of a timer process using a scheduled interrupt. I...Note belt, 11...No Tsutatsujingu, [2
... Winding shaft, 14... Rotation angle detection model wheel, 18...
- Morph, 23...Displacement detection device, 24...Microcomputer, 25...ROM. X...RAM%l...Transistor bridge, 52
... Attachment detection device. Figure 1 Figure 2 Figure 8 Procedural Amendment Form Showa 5th Film J-d To the Commissioner of Japan Patent Office 1, Matter 1'1- Indication of Patent Application No. 154882 of 1988 2. Name of Invention Seatbelt Retractor 3, Relationship with the amended person case Applicant (899) Nissan Motor Co., Ltd. 4, Agent Address: 1-29 Akashi-cho, Chuo-ku, Tokyo, 104, Suiseikai Building (3) ij
Correct the R8 diagram as shown in the attached sheet. Figure 8 2 3

Claims (2)

[Claims] (1) A take-up shaft to which the seat belt end is fixed; a motor that rotates the take-up shaft in the winding direction or the unwinding direction; a displacement detection device that detects displacement in the removal direction and the withdrawal direction; a comparison device that compares the output signal of the displacement detection device with a value set corresponding to a predetermined amount of slack; a mounting detection device that detects the mounting of the device, and based on the output of this device detection device and the comparison device,
a slack control device that rotates the motor in the forward and reverse directions, winds and tightens the excess belt after the seat belt is worn, and provides a predetermined slack after the belt is tightened; or means for reactivating the slack control device after sensing belt withdrawal. (2) A take-up shaft to which the seat belt end is fixed; a motor that rotates the take-up shaft in the winding direction or the unwinding direction; a displacement detection device that detects displacement in the take-out direction and the pull-out direction; a comparison device that compares the output signal of the displacement detection device with a value set corresponding to a predetermined belt slack; and a seat belt attachment device. a mounting detection device that detects the
a slack control device that rotates the motor in the forward and reverse directions, tightens the excess belt after it is attached, and provides a predetermined slack after the tightening; and a predetermined period of time elapses after the operation of the slack control device is completed. means for re-activating the slack control device after detecting belt withdrawal, the position of the 7-toe belt at the time of initial tightening, and the position of the 7-toe belt after re-activation of the slack control device; A belt retractor comprising means for comparing the values and setting the minimum value as the best position of the belt.